GoKawiilUnpatched Calix GS5239XG router flaw exposes home devices to internet
Researcher Brian Khan Quintana found that Calix's GS5239XG (GigaSpire 7u10txg) fiber gateway exposes its UPnP control service on the public WAN interface without authentication, tracked as CVE-2026-75501. Anyone online can send a single unauthenticated request to add or remove port-forwarding rules, letting them bypass NAT and firewall protections. Calix did not respond to disclosure attempts, so CERT/CC coordinated a public release of the details.
GoKawiil's interpretation of the reporting above, not reported fact.
Calix supplies gateways to major U.S. broadband providers like Cox, Brightspeed, ALLO, CityFibre and Conexon, meaning the flaw could affect a large number of residential customers who have no way to patch it themselves. With no authentication required, attackers can silently expose cameras, NAS devices, and admin panels inside homes, turning a single request into a persistent backdoor until Calix issues a fix.
- CVE-2026-75501 lets unauthenticated remote attackers open port-forwarding holes on Calix GS5239XG routers.
- The flaw stems from an exposed UPnP SOAP service on the WAN interface, with no vendor patch yet available.
- Calix ignored disclosure attempts, prompting CERT/CC to publish the vulnerability without a fix in place.
ASUS RT-BE88U Wi-Fi 7 Router — If you'd rather not rely on an ISP-supplied gateway with an unpatched port-forwarding flaw, putting your own Wi-Fi 7 router behind it gives you control over firmware updates, UPnP settings and firewall rules. The RT-BE88U is a well-supported flagship from ASUS with a detailed admin interface for locking down remote access and managing your own NAT.
See ASUS RT-BE88U Wi-Fi 7 Router on Amazon → Affiliate link — we may earn a commission on purchases, at no extra cost to you. Product picked by AI based on this article; it is not a tested recommendation.Source: bleepingcomputer.com, 2026-08-24
Published there as: “Unpatched Calix flaw lets hackers bypass NAT to expose internal devices”
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